1. Field of the Invention
This invention is related to the field of art of the brushless, windingless rotor, variable reluctance, electromechanical alternators and motors having wound-field excitation.
2. Background Information and Prior Art
The invention disclosed herein represents a significant improvement to, and an addition of new matter to the subject matter of the U.S. Pat. No. 5,146,127 to Smith, in the context of an inventive combination. The improvement by the inventive combination and the new matter disclosed are primarily focused on the potential applications of the technologies of the referenced Smith patent, in the areas of direct-current alternator products, single-phase and three-phase power alternators having alternating-current (AC), field-modulated excitation, as well as, electronically commutated (EC), direct-current, controlled drive motor products.
The disclosure by the U.S. Pat. No. 5,146,127 to Smith did not provide for a means, nor method, to substantially negate the undesirable harmonics in the currents of the field excitation circuits, that are the result of the back electromotive force, or back-EMF, generated in the field windings by the varying magnetic field pole fluxes. This field current harmonic condition results in undesirable harmonic distortion in the induced armature, open-terminal, output voltage waveform. Furthermore, the harmonics in the field currents and the armature, open-terminal, output voltage, interactively reduce machine efficiency; reduce the quality of the armature output-voltage waveform from the desired square-wave form, and introduce undesirable operational torque characteristics.
The means and methods disclosed herein, which consist of a combination of (1) a unique construction format for the rotor and stator embodiments, and (2) the connection schemes for the field windings, whereas, the combination is essential to substantially negate the aggregate back EMF of the field windings, to minimize the harmonic content of the field excitation currents, were not considered in the disclosure by Smith.
In addition to the unique construction format and the unique connection schemes for the field excitation windings, which are disclosed in the inventive combination, there is still another significant improvement disclosed herein that would add new matter to the disclosure in U.S. Pat. No. 5,146,127 to Smith. That is, the aggregate inductance of the field excitation windings and circuits would be substantially constant in magnitude; complementing the efforts to reduce the harmonics in the currents and EMF waveforms in both the field windings and armature windings circuitry.